Jason Morelli
From Halopedia, the Halo wiki
Jason Morelli aka The Castaway is Jersey Morelli's father, a signalman in the Navy, has been away for over a year and a half. He is attached to Naval Intelligence, Radio Beacon Deployment Program, current tour of duty 513 days as of the date that Durga is found by Jersey Morelli. Likes classical/jazz music.
When Reach was glassed, Jason was assigned to a ship named the UNSC Silberg on a deep-space reconnaissance assignment.
In a live telephone call on October 19, Melissa confirmed that Jason is, in fact, the man she refers to as the The Castaway.
References
Partial transcript of Jersey.wav
Durga:...Give me a target Jersey: Me Durga:Lock Jersey:What's my name? Durga:Jersey Morelli... Jersey:DAMN!! Durga:Father Jason is a corporal in the signal core attached to Naval intelligence, Radio beacon deployment program. He left you the material currently playing over this room's audio servers.
